Windows 9 will also arrive in different forms for different types of hardware devices.

For phones and tablets where app tiles make sense for touch input, Windows 9 will default to this layout. For desktop and laptop users, Windows 9 will automatically default to a traditional layout akin to Windows 7, with the added Mini-Start Menu.

Hybrid devices, such as Microsoft's Surface Pro tablet, will reportedly boot a desktop-style layout if it senses a keyboard attached, otherwise defaulting to the touch-oriented app tiles.

Microsoft isn't done updating Windows 8, but Windows 9 Threshold will reportedly launch around spring 2015, with a public preview arriving this fall.